EP0361051A2

EP0361051A2 - CRT socket

Info

Publication number: EP0361051A2
Application number: EP89115009A
Authority: EP
Inventors: Atsushi Arai
Original assignee: SMK Corp
Current assignee: SMK Corp
Priority date: 1988-08-29
Filing date: 1989-08-14
Publication date: 1990-04-04
Also published as: JPH0234095U; JPH0539596Y2; EP0361051A3

Abstract

Disclosed is a CRT socket comprising a socket housing, a focus connection contact and a focus spark-gap contact, which has a snap-in terminal to connect to a high-voltage lead conductor. This snap-in terminal is composed of stationary and movable contact pieces. The socket housing has a spark electrode compartment and a socket cover. The socket cover has a hollow casing to contain the snap-in terminal of the focus spark-gap contact and a press-fit cover to close the hollow casing. The press-fit cover has a projection to enter the hollow casing and push the movable contact piece against the stationary contact piece when closing the hollow casing. This CRT socket structure permits first, checking by sight of the connection of a high-voltage lead conductor to the focus spark-gap contact, and second, easy removal of the high-voltage lead conductor from the CRT socket for maintenance or checking simply by opening the press-fit cover.

Description

The present invention relates to a cathode ray tube or CRT socket comprising a housing, a focus connection contact and a focus spark-gap contact, these contacts along with other necessary contacts being built in the housing.
Figs. 11 and 12 show a conventional CRT socket. As seen from these drawings, a focus connection contact 2 and focus spark-gap contacts 3 and 4 along with other necessary contacts are built in a socket housing 1. The focus connection contact 2 has a resilient terminal piece 2a at its end. As shown, the resilient terminal piece 2a is formed by folding the end of the strip conductor. The focus spark-gap contact 3 or 4 has a spark electrode 3a and a terminal piece 3b. These terminal pieces are arranged to confront each other. As shown in Fig. 13, the core end 5a of a high-voltage lead conductor 5 is inserted between these terminal pieces 2a and 3b, together constituting a snap-in terminal. The spark electrode 4a of the focus spark-gap contact 4 is positioned a predetermined distance apart from the spark electrode 3a of the focus spark-gap contact 3 in confronting relation.
The terminal piece 2a has a very strong resilient force to push the core end of the high-voltage lead conductor 5 against the terminal piece 3b lest the core end 5a of the high-voltage lead conductor 5 should slop off from the snap-in terminal. Therefore, once the core end 5a of the high-voltage lead conductor 5 has been inserted in the snap-in terminal, it cannot be pulled out and removed.
The hook-like shape of the terminal piece 2a makes it still more difficult to remove the core end 5a. Maintenance and checking work, however, necessitate removal of the high-voltage lead conductor. In this connection the conventional structure is inconvenient in maintenance and checking work. Also, disadvantageously the conventional structure does not permit a person to check by sight whether the core end of the high-voltage lead con ductor has been fully pushed into the snap-in terminal.
With the above in mind one object of the present invention is to provide a CRT socket structure which permits easy removal and subsequent insert of the core end of a high-voltage lead conductor into an associated snap-in terminal, and permits checking by sight of connection to the high-voltage lead conductor.
To attain this object a CRT socket comprising a socket housing, a focus connection contact and a focus spark-gap contact, these contacts along with other necessary contacts being built in said socket housing, said focus connection contact being connected to said focus spark-gap contact and to a high-voaltage lead conductor, is improved according to the present invention in that: said focus spark-gap contact has a snap-in terminal to connect to said high-voltage lead conductor, said snap-in terminal being composed of a stationary contact piece and a movable contact piece, confronting each other, said socket housing having a spark electrode compartment opening upwards and containing the spark electrode of said focus spark-gap contact, and said socket housing having a socket cover detachably fixed to said spark electrode compartment to close it, said socket cover having a hollow casing to contain the snap-in terminal of said focus spark-gap contact with its stationary contact piece fixedly held in position in said hollow casing, and said socket cover having a press-fit cover to close said hollow casing, said press-fit cover having a projection to enter said hollow casing and push said movable contact piece against said stationary contact piece when closing said hollow casing.
In removing the core end of a high-voltage lead conductor from the confronting stationary and movable contact pieces of the snap-in terminal of the focus spark-gap contact, the press-fit cover is opened to put the movable contact piece apart from the stationary contact piece of the snap-in terminal, thereby putting the core end of the high-voltage lead conductor in stress-free condition. In connecting the core end of the high-voltage lead conductor to the snap-in terminal, the core end of the high-voltage lead conductor is placed between the stationary and movable contact pieces of the snap-in terminal, which pieces separate a distance enough to allow the inserting of the core end. The insertion of the core end can be checked by sight. Then, the press-fit cover is closed so that its projection may push the movable contact piece, thus assuring reliable connection of the high-voltage lead conductor to the snap-in terminal of the focus spark-gap contact.
Other objects and advantages of the present invention will be understood from the following description of a CRT socket according to one embodiment of the present invention, which is shown in accompanying drawings:

Fig. 1 is a side view of the CRT socket partly broken to show the inside;
Fig. 2 is a plane view of the CRT socket;
Fig. 3 is an end view of the CRT socket as seen from the left of Fig. 2;
Fig. 4 is a side view of the focus connection contact used in the CRT socket;
Fig. 5 is a side view of the focus connection contact as seen from the left of the contact of Fig. 4;
Fig. 6 is a plane view of the focus connection contact as seen from the top of the contact of Fig. 4;
Fig. 7 is a front view of the focus spark-gap contact used in the CRT socket;
Fig. 8 is a side view of the snap-in terminal of the focus spark-gap contact as seen from the left of the contact of Fig. 7;
Fig. 9 is a plane view of the snap-in terminal of the focus spark-gap contact as seen from the top of the contact of Fig. 7;
Fig. 10 is a longitudinal section taken along the line X-X of Fig. 7;
Fig. 11 is a plane view of a conventional CRT socket;
Fig. 12 is a longitudinal section of the conventional CRT socket; and
Fig. 13 is a section of a part of the conventional CRT socket, showing how a high-voltage lead conductor is connected to the focus spark-gap contact.

Figs. 1 to 10 show a CRT socket according to one embodiment of the present invention. A focus connection contact 12 has press contact terminal pieces 12a and 12b. These pieces are formed by bending the end of a strip conductor in the form of inverted "U" shape and making a slot 12c in the folded end ( See Figs. 4, 5 and 6 ).
A focus spark-gap contact 13 has a spark electrode 13a, a lateral extension contact 13b to connect the press contact terminal of the focus connection contact and a snap-in terminal 13c to connect a high-voltage lead conductor 5 (See Figs. 7, 8 and 9). The snap-in terminal 13c comprises a stationary contact piece 13c₁ and a movable contact piece 13c₂. The movable contact piece 13c₂ is formed by folding a lateral extension of the conductor strip, and the folded contact piece 13c₂ confronts the stationary contact piece 13c₁. A high-voltage lead conductor 5 can be connected to the focus spark-gap contact 13 by inserting its core end between the confronting stationary and movable contact pieces 13c₁ and 13c₂. The movable contact piece 13c₂ had an outward inclination 13c₃ and an inner-bent top 13c₄.
As shown in Fig. 1, a socket housing 11 has a spark electrode compartment 11a opening upwards. It contains the spark electrode 13a of the focus spark-gap contact 13. A socket cover 10 is detachably fixed to the spark electrode compartment. The socket cover body 15 has a hollow casing 16 to contain the snap-in terminal of the focus spark-gap contact with its stationary contact piece 13c₁ fixedly held in position.
Also, the socket cover 10 has a press-fit cover 17 hinged to the cover body 15 as indicated at 18 to close the hollow casing 16. As best shown in Fig. 2, the press-fit cover 17 has a notch 17a. A high-voltage lead conductor 5 can be put in the notch 17a, thereby permitting the press-fit cover 17 to be completely closed and locked to the socket cover body 15 with locking means 19 and 20. The press-fit cover 17 has a projection 21 to enter the hollow casing 16 and push the movable contact piece 13c₂ against the stationary contact piece 13c₁ when closing the hollow casing 16. The projection 21 has an inclined surface 21a, thereby assuring the smooth insertion of the projection 21 in the hollow casing 16.
The hollow casing 16 has a rectangular form in cross section. The stationary contact piece 13c₁ is pushed against one wall 16a of the rectangular frame, and is fixedly held. The hollow casing has a receptacle 16b for accepting a high-voltage lead conductor on its side. The receptacle 16b has a tapering hole 16b₁ and a guide piece 16d for guiding the insertion of the core end of the high-voltage lead conductor.
As may be understood from the above, a CRT socket according to the present invention when used, permits checking by sight of the insertion of the core end of an associated high-voltage lead conductor 5 between the stationary and movable contact pieces 13c₁ and 13c₂ of the focus spark-gap contact. The core end of the high-voltage lead conductor 5 can be pinched and firmly held between the stationary and movable contact pieces 13c₁ and 13c₂ against the stationary contact pieces 13c₁.
If removal of the high-voltage lead conductor from the CRT socket is desired for maintenance or checking, the press-fit cover 17 is opened to remove its projection 21 from the hollow casing 16, thereby putting the stationary and movable contact pieces 13c₁ and 13c₂ in stress-free condition in which the core end of the high-voltage lead conductor 5 can be easily removed. Also, in this stress-free condition the core end of the high-voltage lead conductor 5 can be easily inserted between the stationary and movable contact pieces 13c₁ and 13c₂.

Claims

A CRT socket comprising a socket housing, a focus connection contact and a focus spark-gap contact, these contacts along with other necessary contacts being built in said socket housing, said focus connection contact being connected to said focus spark-gap contact and to a high-voltage lead conductor, characterized in that:
said focus spark-gap contact has a snap-in terminal to connect to said high-voltage lead conductor, said snap-in terminal being composed of a stationary contact piece and a movable contact piece, confronting each other, said socket housing having a spark electrode compartment opening upwards and containing the spark electrode of said focus spark-gap contact, and said rocket housing having a socket cover detachably fixed to said spark electrode compartment to close it, said socket cover having a hollow casing to contain the snap-in terminal of said focus spark-gap contact with its stationary contact piece fixedly held in position in said hollow casing, and said socket cover having a press-fit cover to close said hollow casing, said press-fit cover having a projection to enter said hollow casing and push said movable contact piece against said stationary contact piece when closing said hollow casing.